Wire tensioning device



Original Filed Oct. 1, 1938 May 25, 1943;

M o 0 T 5. N /F .16 4 M w w fix 0 3 4. 14W w 4 WWW I n m 7 4 M PatentedMay 25, 1943 WIRE TENSIO-NIN G DEVICE Penrose E. Chapman, Sr., St.Louis, Mo.

Original application October 1, 1938, Serial No. 232,715, now Patent No.2,242,053, dated May 13, 1941. Divided and this application Januany 21,1941, Serial No. 375,315

3 Claims.

This application is divided out of my application No. 232,715, series of1935, filed October 1, 1938, now Patent No. 2,242,053, dated May 13,1941.

The object of my invention is applying an automatic compensated tensionto wire so that the final or delivered tension shall be practicallyuniform.

I accomplish this object as hereinafter described.

The term wire is herein used to include any elongated material ascordage, wire, ribbon, et cetera, made of any material.

In the drawing Fig. 1 is a general front elevation of my automatictension device.

Fig. 2 is a left edge elevation of the said automatic tension device.

Fig. 3 is a vertical sectional view taken approximately on the planeindicated by the line 33 of Fig. 1.

The accomplishing of my object to deliver wire under uniform tensionrequires that any tensioning device be self-adjusting, like a governor,and compensate for the irregularities of tension in the wire as fed tosaid device and those caused by erratic demand.

To provide the tension I movably mount a capstan pulley 4| upon a crank42. The shaft of this crank is supported in the bearing 42' in the frame40. By capstan pulley is meant one simulating or derived from thewell-known ship capstan, having a convex or straight-tapered tread aboutwhich one or more convolutions of the wire or filament intermediate theends thereof are wound, which tread, because of its taper, causes theconvolutions to continuously slip axially thereon toward the smallestdiameter as the one end portion of the wire is withdrawn from and theother end portion is supplied to the tread. The tread 4| of the capstanpulley may be of any conventional pattern but I prefer it tapered in theusual manner.

A brake shoe 46 is arranged to act against the tread of said capstanpulley. Said shoe is shown in section in Fig. 2. This brake shoe isflexibly mounted as by the brake shoe spring 41 that is convenientlyattached to the lug 40 of the frame 40.

The capstan pulley 4| is pressed against said brake shoe 46 by thetension spring 43 which has one end attached to crank 42 and the otherthrough any convenient adjusting means as nut 44 and screw 44' to thebracket 45 carried by the frame 40.

In action the wire ll emerges from the apex 35 through the wiredirecting guide 36 and is deposited by it upon the high side of thecapstan pulley tread at l I, then wraps around said pulley and leavesthe lower side of the tread approximately in the direction of the motionof said pulley. With this arrangement the wire is gripped between thebrake shoe 46 and the tread 4| of the capstan pulley as shown in sectionin Fig. 2 thus supplying the friction or drag necessary in applying atension to said wire. As the wire ll slips down the tread 4| of thecapstan pulley in the usual manner it also slips across the face of thebrake shoe and thereby avoids wearing serious grooves therein.

The automatic regulation or governing of the tension is accomplished asfollows: As stated the capstan pulley is pressed against the brake shoeby the spring 43. The direction of the pull of the wire going to andleaving the pulley is opposed to the action of said spring upon saidpulley so that as the tension on either or both the entering or leavingwire increases it tends to neutralize more or less the tension of saidtension spring and retract or pull said pulley away from said brakeshoe, thus easing off or releasing the braking action of the said brakeshoe. When tension on wire decreases obviously the reverse actionoccurs.

There may be many modifications of the physical structure I have used todisclose this one of my inventions that may be used without departingfrom said invention, therefore as my invention I wish to claim:

1. In a device for automatically controlling the tension on a filamentor the like being continu ously withdrawn from a source of supply, arotatably mounted wheel having an axially tapering tread about which thefilament is helically trained; and a brake member engageable with thefilament to press it against the wheel tread, at least one of theelements being yieldably mounted to provide tension-responsive pressurebetween the brake member, filament and wheel tread, and the taper of thetread effecting axial slippage of the filament thereon toward thesmaller diameter as said filament is supplied to and withdrawn from thetread, whereby the filament is moved across the face of the brake memberto distribute the wear thereon.

2. In a device for automatically controlling the tension on a filamentor the like being continuously delivered from a source of supply, arotatable capstan wheel to which the filament is continuously suppliedand from which it is continuously withdrawn, said wheel having anaxially tapered tread about which convolutions of the filament aretrained; a brake shoe mounted for engagement with said convolutions; andmeans responsive to variations in the tension upon the filament forcausing variable pressural engagement between the brake shoe andconvolutions to cause the'shoe to continuously press the convolutionsagainst the wheel tread and to resist rotation of the wheel; the taperof the tread producing axial movement of the convolutions thereon as thefilament is supplied to and. withdrawn from the same, whereby theconvolutions are moved across the face of the shoe and localized wear ofthe latten prevented.

3. A device for automatically controlling. the tension on a filament orthe like being continuously delivered from a source of supply,comprising a rotatable capstan wheel having an axially tapering tread,to a larger diametral portion of which the filament is continuously fedand from a smaller diametral portion of which it is continuouslywithdrawn, with convolutions encircling the tread between said portions;a brake shoe mounted for engagement with said convolutions; and yieldingmeans for causing pressural engagement between the brake shoe, filamentconvolutions and wheel tread to resist rotation of the convolutions andwheel, said means being responsive to variations in the tension upon thefilament to vary the pressure between the shoe, convolutions and treadaccordingly; the taper of the wheel tread causing axial slippage of theconvolutions thereon as the filament is supplied to and withdrawn fromthe same, whereby the convolutions are moved transversely across theface of the shoe and localized wear of the latter is prevented.

PENROSE E. CHAPMAN, SR.

